Encoding insignificant whitespace of XML data

• US 20080098019A1
• Filed: 02/16/2007
• Published: 04/24/2008
• Est. Priority Date: 10/20/2006
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle International Corporation (Oracle Corporation)
• Inventors: Idicula, Sam, Agarwal, Nipun, Sthanikam, Balasubramanyam, Chandrasekar, Sivasanakan
• Granted Patent: US 7,627,566 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/258 Data format conversion from or to a database
• CPC Class Codes: G06F 16/81 Indexing, e.g. XML tags; Data structures therefor; Storage structures
• CPC Class Codes: Y10S 707/99934 Query formulation, input preparation, or translation
• CPC Class Codes: Y10S 707/99942 Manipulating data structure, e.g. compression, compaction, compilation
• CPC Class Codes: Y10S 707/99943 Generating database or data structure, e.g. via user interface

Abstract

Techniques are described for preserving the original insignificant white space of XML data. The techniques may be used in combination with compact XML data storage formats, such as binary XML, to preserve the insignificant white space without requiring as much storage space as uncompressed formats. White space opcodes/operand pairs are described for representing white space characters and white space patterns. The white space opcode/operand pairs represent the white space in binary XML, are use to generate the original white space when the binary XML is decoded back to textual XML data.

Claims

1. A method for encoding insignificant white space of XML data, the method comprising:

identifying an occurrence of insignificant white space in the XML data;

generating one or more opcodes and one or more corresponding operands to represent the occurrence of insignificant white space;

reconstructing a version of the XML data that includes the occurrence of the insignificant white space based on (a) the one or more opcodes and one or more corresponding operands, and (b) information that represents the XML data without the insignificant white space.

2. The method of claim 1 further comprising, after generating the one or more opcodes and one or more corresponding operands, storing the one or more opcodes and one or more corresponding operands in a database, wherein the database also stores the information that represents the XML data without the insignificant white space

3. The method of claim 1 wherein the information that represents the XML data is binary XML.

4. The method of claim 3 wherein the one or more opcodes and one or more corresponding operands are stored as part of the binary XML that represents the XML data.

5. The method of claim 1 wherein the step of reconstructing a version of the XML data includes decoding the binary XML with a decoder that:

generates tokens based on replacement values contained in the binary XML; and

generates insignificant white space based on white space opcodes and white space operands contained in the binary XML.

6. The method of claim 1 wherein the one or more opcodes includes an opcode that indicates a size of a corresponding operand that follows the one or more opcodes.

7. The method of claim 1 wherein the one or more operands includes an operand that includes a type portion that indicates what type of whitespace is contained in said occurrence.

8. The method of claim 7 wherein the type portion indicates a particular type of whitespace character.

9. The method of claim 7 wherein the type portion indicates a particular type of whitespace pattern.

10. The method of claim 1 wherein the one or more operands includes an operand that includes a count portion that indicates how many times a particular white space character is repeated in said occurrence of white space.

11. The method of claim 1 wherein the one or more operands includes an operand that includes a count portion that indicates how many times a particular white space pattern is repeated in said occurrence of white space.

12. The method of claim 1 further comprising storing, with the information that represents the XML data, a flag that indicates whether insignificant white space is included in the information that represents the XML data.

13. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 1.

14. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 2.

15. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 3.

16. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 4.

17. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 5.

18. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 6.

19. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 7.

20. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 8.

21. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 9.

22. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 10.

23. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 11.

24. A computer-readable medium carrying one or more sequences of instructions which, when executed by one or more processors, causes the one or more processors to perform the method recited in claim 12.